Is jeweled on one barrel arbor. I wanted to touch on the 25 jeweler, but it sliped my mind. Where the one more jewel is, I`m not sure, it could be on the escapewheel bottom plate, or is likely the bottom barrel arbor, either of these choices would be good. I would hold the 25 jeweler to a higher collector value, but cant put a price on it. They are much rarer then the 23 jeweler.
About B-C accuracy standards.
According to the seiko book, the B standard was +15/-10. The C standard was +25/-15.
One big difference between the two streams, the 56, and the 52, was the 52 was made to beat at 28.8kbph. This, in and of itself, enabled a higher accuracy standard. This is the reason for the 52 being rated at a B standard. Consequently, its no suprise that the 4s15 has these same specs, having been a complete resurection of the 52 stream.
Regards Don, and enjoy your holiday.
Randall
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